Consumption Figures Accurate?

I am still trying to sell my sailboat and buy a trawler. I have a hard time believing some of the consumption figures.

Here is my question......

I looked at a 40' Mainship Trawler on Yachtworld.com

Specs show Twin 165 Perkins* Model:Turbo

Cruising Speed = 10K**** Max Speed = 18K

Fuel: 300 Gallons

It then shows maximum Range in NM = 1500

This equates to 5 NM/gal. I am pretty sure that if this is possible it wont be at 10Kts.

Is this 5nm/gal possible at even 5 or 6kts?

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I know tons of Mainshippers with those engines and that is wishful thinking. That must be a Pilot House model circa 1981/82?

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It is a 1980 Sedan/Europa Model.

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If its the one in Lake Charles, that is a Pilot House model as it was called when it was built.

The engines are Perkins 160 hp. That is the old model engines. The 165 hp range 4 series came out in 1981.

Likely one is reverse rotation and some parts for those are hard to find.

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In short no. It is impossible for a 40' Mainship with her semi-displacement hull to do anything like 5nmpg. Best case at 1400 rpm is more like 3nmpg.

No way.**

Here's what Mainship writes about their*1980-1984,**40 foot motor cruiser and fuel economy; "Twin 165-hp Perkins diesels will cruise efficiently at 10-11 knots (15 knots top) burning about 1 gph."* I wonder who writes this stuff.

http://www.mainship.com/models/previous_models/40mc.htm

Larry M wrote:
No way.**

Here's what Mainship writes about their*1980-1984,**40 foot motor cruiser and fuel economy; "Twin 165-hp Perkins diesels will cruise efficiently at 10-11 knots (15 knots top) burning about 1 gph."* I wonder who writes this stuff.

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Click to expand...

About the same engines, more HP, as mine and I burn closer to 7gph at that speed. *They must have a built in anti-gravity/friction machine or maybe just a typo.***

if i rember right when i* delivered when they were new,we used to get i mile per gallon on trips to florida* from jersey doing 11 or 12 knots, but at my age i could be wrong

jleonard wrote:
If its the one in Lake Charles.....

The engines are Perkins 160 hp. That is the old model engines. The 165 hp range 4 series came out in 1981.

Likely one is reverse rotation and some parts for those are hard to find.*

Click to expand...

*Yes, it is the one in Lake Chas. My wife is in Ms. helping out her family. She will be driving home Friday to meet me in Lake Chas. on my way home from Offshore to take a look at it.

Assuming the best I could get out of that would be 3 nm/gal. What would I expect to get from twin Ford Lehman's with 120 HP each?

To move that boat at*X speed it will take a certain amount of horsepower.

It doesn't matter which engine you use to power it they will be very close to the same fuel consumption, esp with engines of the same general vintage.

FL 120s are no more efficient than Perkins T6.354s.

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"FL 120s are no more efficient than Perkins T6.354s."

Probably at trawler cruise speed, , but a turbo engine , RUN HARD ENOUGH , will be more efficient than a NA.

Weather the maint cost will ever get repaid at trawler fuel burn is a great question.

Since it IS a question , the higher parts count and maint would make a NA my first choice.

KISS

What is the most powerful NA engine available in the US?*

"What is the most powerful NA engine available in the US? "

Newer engines will frequently have turbos for the air police, even on tiny sizes.

A DD V 16-71 can produce 20 -30 hp per cylinder , that's almost 500hp cont , more than most trawler folks want to feed.

FF,

Show me an engine under 50hp that has a turbo.

I know of none.

What is the most powerful NA engine available in the US?

Show me an engine under 50hp that has a turbo.

Strange combination of questions?

The new diesel car engines will probably be the source for boat engines in the future.

The Yanmar ,,,Toyota and BMW based donors currently come to mind.

The hassle so far is the auto ratings are not realistic , a BMW might be 200-400hp for a drag race , but probably 1/5 that with 24/7 endurance in mind.

Under 50 hp is gen set and yard equipment power , don't worry the air police will be visiting (I believe the Euros already have) so the complex costly crap like will be coming.

It will be interesting to see how turboes and $1000 injectors and $6000 brain boxes cam be down marketed on lawn mowers , it will be a techies delight for the next few years .